The present invention relates to a novel zeolite catalyst and a process for the preparation thereof.
Zeolites having various structures have heretofore been prepared and uses therefor are being extensively studied. Some new types of zeolite have been developed in recent years. Japanese Patent Application Laid-Open No. 95822/1982, for example, discloses crystalline aluminosilicate which is prepared by subjecting a starting material consisting of two types of colloid having different silica/alumina ratios to a hydrothermal reaction and in which the composition of the inner portion or core is different from that of the outer portion or shell. At present the production of ethylene from methanol using the crystalline aluminosilicate as a catalyst is being studied. Japanese Patent Application Laid-Open No. 191223/1982 discloses crystalline silicate zeolite of the structure comprising the core made of crystalline silicate and the shell made of crystals containing aluminum. This crystalline silicate zeolite is used in the polymerization of olefins.